Kururi Castle (久留里城 Kururi-jō) is a Japanese castle located in Kimitsu, southern Chiba Prefecture, Japan. At the end of the Edo period, Kururi Castle was home to a branch of the Kuroda clan, daimyō of Kururi Domain. The castle was also known as Rain Castle (雨城 U-jō?), after a legend that it rained twenty-one times during its construction, or, on average, once every three days.[1]